Faelz, a 14-year-old freshman at Foothill High School, was wounded 44 times in the fatal attack, stabbed in her back, chest, neck and torso, cut on her face, and suffered cuts that medical examiner Thomas Rogers described as "consistent with defensive wounds."
Rogers testified that Faelz died of "multiple stab wounds and incised wounds" from what was likely a single-edged 3-1/2- to 4-inch knife; both her carotid artery and jugular vein were severed in the attack.
Carlson, now 44, has pleaded not guilty to Faelz's murder. He was arrested last year in the 28-year-old case after what police described at the time as a fresh look at evidence. New DNA testing methods led them to Carlson, who has a lengthy criminal history and is a registered sex offender.
In court Tuesday, Carlson, dressed in a red Alameda County Jail outfit, watched his former friend testify about his behavior on the day Faelz was killed.
Todd Smith told the court that Carlson normally had a fascination for the gruesome, but opted that day to stay at his home after neighborhood teens, classmates of all three, discovered the body.
"Anything that was exciting, he wanted to be part of, know what was going on," Smith testified, adding that Carlson's attraction to the morbid extended to throwing live lizards into the family's garbage disposal.
When Smith told Carlson that a body had been found near a culvert used as a shortcut by Foothill high students, "He said he wasn't going down there," Smith told the court.
Smith noted that Carlson had changed into shorts and that his hair was either wet or greasy.
"He had clean clothes on and appeared to be clean," Smith testified.
Carlson, he said, referenced Faelz when he threatened to kill his younger brother when the two went to Carlson's home that day.
"He said, 'Come here, little boy, let me kill you like I killed her," Smith told the court. He said that led to him punching Carlson, then calling the police to report what he'd heard.
He said the officer who answered the phone didn't take him seriously.
"I remember clearly, he said, 'Thanks a lot, kid,'" Smith testified.
However, defense attorney Cameron Bowman noted that there was no record of that call.
Bowman also pressed Smith on differences between his initial statements to police -- when Smith was among the suspects in the case -- prompting Smith to say a number of times that he either could not remember what he'd told police or, in some cases, not remember the interview at all.
The defense attorney also pushed Smith about inconsistencies about that date Carlson made the comment about "killing her." He pointed to police interviews over the course of three weeks, and asked why Smith hadn't brought up the threat Carlson had made during any of those interviews.
Bowman also noted that Smith called his memory "hazy" in a 1986 interview with police.
Smith admitted under questioning that he has a felony record for possession of stolen merchandise and several misdemeanor convictions as well.
A preliminary hearing is not an indication of guilt; based on the evidence, Superior Court Judge Larry Goodman will decide whether there is enough evidence to hold a trial.